Fluid flow control apparatus



Aug. 31, 1965 Filed Aug. 13, 1962 Po. l.

'humm' J. REGAN ETAL FLUID FLOW CONTROL APPARATUS 3 Sheets-Sheet lINVENToRs. JOHN REGn/v LEQOY M/Lse Aug. 31, 1965 Filed Aug. l5, 1962fra.

J. REGAN ETAL FLUID FLOW CONTROL APPARATUS 3 Sheets-Sheet 2 /aINVENTORS.

ci/nv RESA/v Lf-@oy 1l/Lesa Aug. 31, 1965 J. REGAN ETAL 3,203,358

FLUID FLW CONTROL APPARATUS Filed Aug. 13, 1962 3 Sheets-Sheet 5INVENToRs. :kA/N Been/v LEQOY Afl/LER United States Patent O 3,203,358FLUID FLOW CONTROL APPARATUS John Regan, Rolling Hills Estates, andLeRoy Miller, Los

Angeles, Calif., assignors to Regan Forge & Engineering Co., San Pedro,Calif., a corporation of California Filed Aug. 13, 1962, Ser. No.216,478 11 Claims. (Cl. 10S- 203) This invention relates in general toapparatus for removing well lluid from wells employing a reservoirbetween the tubing and casing walls to receive well lluid preparatory tointroduction into a well pump. More particularly, the invention relatesto the provision of a reservoir lluid level control device adapted foruse in such apparatus for maintaining the level of iluid in suchreservoir at a predetermined level.

In recovering oil from oil wells employing a bottom hole pump, it hasbeen found that, because of the high gas saturation of the well tluidfrequently encountered, it is difficult to pump the lluid to the surfacein its natural state. Also, very high well pressures generally exist insuch instances of high gas saturation, making it diilicult to handle theiluid in attempting to reduce the gas saturation. One way of handlingsuch high pressure, highly gas saturated lluid, is to introduce'the welllluid into a reservoir formed between the casing and tubing walls of thewell apparatus under conditions of low uid pressure, allowing the gas tocome out of solution and pass up the casing annulus and the liquid oilto settle to a well pump inlet where it is pumped to the surface.However, when very high well pressures are encountered and the well isvery deep, the rush of well lluid into the reservoir may cause thereservoir lluid level to rise several hundreds of feet, creating veryhigh lluid pressures within the reservoir at the point the iluid entersthe reservoir.

The high pressure at the reservoir inlet tends to retard the separationof gas from the well lluid as it is introduced into the reservoir.

It is, therefore, the principal object of the invention to disclose andprovide an apparatus for handling high pressure, highly gas saturatedwell iluid when introducing such lluid into a well apparatus reservoir.

It is a primary object of the invention to disclose and provide areservoir iluid level control device for use in an apparatus forremoving well lluid from wells ernploying a reservoir for receiving wellfluid preparatory to introduction into a well pump wherein llow of welliluid under relatively high well pressures to the reservoir may beeasily controlled in response to changes in the relatively smallerpressures in the reservoir.

It is another object of the invention to disclose and provide a lluidilow control apparatus adapted to balance most of the forces of highpressure lluid llowing therethrough through opposed, interconnectedvalve means wherein such valve means are hydrostatically slightlyunbalanced to cause iluid llow through the apparatus to urge said valvemeans into a closed position under a resultant force thereonconsiderably less than the total amount of force exerted on said opposedvalve means.

It is a further object of the invention to disclose and provide a liquidlevel control device to control the passage of high pressure well lluidinto a well apparatus reservoir which may be disposed in an upperportion of the reservoir, be interconnected with the source of welllluid by vertical passage means extending upwardly within the reservoirand which may be readily operated by changes in the relatively smalleruid pressures in the upper portion of the reservoir.

It is a still further object of the invention to disclose and provide awell apparatus for recovering well fluid from a well including areservoir to receive well iluid 3,203,358 Patented Aug. 31, 1965 icepreparatory to introduction into a well pump in which apparatus forcontrolling the tlow of well iluid through valve means therein andpressure sensitive means operable in response to reservoir lluidpressures to operate the valve means may be readily removed from thewell apparatus without disturbing the casing and tubing walls of thewell apparatus.

Generally stated, the invention contemplates the provision of a fluidcontrol device and associated vertical passage means in a well apparatushaving spaced, vertical casing and tubing walls forming a reservoir toreceive well lluid under high pressure and high gas saturation. Thecontrol device maintains the iluid level within the reservoir at below apredetermined level, maintaining iluid pressures in the reservoiradjacent the outlet of the control at relatively low pressures,promoting the separation of gas out of the well lluid. Vertical passagemeans convey the well fluid to an upper portion of the reservoir -suchthat the settling liquid or oil may pass downwardly in the reservoirunder increasing lluid pressures to the inlet of a deep well pump. Thecontrol device may be provided at an upper end of the vertical passagemeans. The control device preferably comprises a generally cylindricalvalve body having an inlet to receive the well lluid under highpressures from the vertical passage means and a pair of outletsvertically spaced on either side of the inlet. Valve means are providedin the body by disposing a pair of axially spaced valve poppets inalignment with a pair of ported valve seats opening to the valve bodyoutlets. Fluid llow through the valve body may thus be directed throughopposed valves in generally hydrostatically balanced relation. Theopposed valves, however, are preferably so provided that a slightunbalancing of the hydrostatic pressures exerted thereon by the lluidtlow is effected. This slight unbalancing of the pressures on theopposed valves does not reduce the ease of operation of the valve meansand provides a snap `action of the valve means upon opening.

A pressure chamber body is provided on an upper portion of the valvebody having an enclosed pressure chamber adapted to receive a charginggas. A lower wall of such chamber, according to the invention, isprovided with diaphragm means operably associated with the valve poppetsin the valve body. The diaphragm means is adapted to react in responseto changes in reservoir fluid pressures under the constant bias of thepressure chamber gas. In addition, a secondary seal may be providedbetween the diaphragm means and the reservoir luid to facilitate a snapaction operation of the valve when iluid pressure in the reservoir risesabove a predetermined value.

In an alternative embodiment of the invention, a special tubing nippleis hung on the bottom end of the tubing `string in a well apparatus atthe approximate location of a bottom hole pump. The tubing nipple has agenerally smooth interior and has vertically spaced apertures therein.The vertical passage means in this embodiment are provided in two partsupon the exterior of the tubing nipple, including a primary passageconnecting a tubing inlet aperture with the supply of well fluid and asecondary passage connecting two verticallyspaced tubing outletapertures with an upper portion of the reservoir. A lluid level controldevice, generally as hereinbefore described, may be removably loweredwithin the tubing nipple, as by a Wire line or hung from the bottom holepump, with its inlet aligned generally with the tubing inlet apertureand the vertically spaced outlets generally aligned with the tubingoutlets. Well fluid under high pressure may then rise through thevertical passage means and intermediary, removably disposed controldevice to an upper portion of the iluid reservoir.

vopen to the well fluid of the well.

Further objects and various advantages of our invention will becomeapparent and a complete understanding of the nature of the inventionwill be facilitated by the consideration of the following detaileddescriptions of an exemplary embodiment of an apparatus for removingwell fluid employing the fluid level control device and vertical passagemeans, according to the invention. Reference will be made to theappended sheets of drawings in which:

FIG. l is a vertical sectional view of a well apparatus, including awell uid receiving reservoir between well casing and tubing string wallsemploying an exemplary embodiment of apparatus for handling the ow ofwell fluid into the reservoir, according to the invention;

FIG. 2 is a detail view in section of the liquid level control device ofthe apparatus for handling the ow of well fluid of FIG. l;

FIG. 3 is a vertical, sectional view of a well apparatus including awell fluid receiving reservoir between well casing and tubing stringwalls employing an alternative exemplary embodiment of apparatus forhandling the flow of well fluid into the reservoir, according to theinvention;

FIGS. 4 and 4a are a detail, sectional view of the removable liquidlevel control device of FIG. 3; and

FIGS. 5 and 5a are a detail, sectional view of the kspecial tubingnipple and alternative form of vertical passage means employed with theliquid level control device of FIGS. 4 and 4a, but with au alternativemeans of interconnecting the control device and the well pump.

An exemplary embodiment of the apparatus for removing well fluid from awell including a reservoir fluid level control means, according to theinvention, is shown in FIGS. 1 and 2. Referring iirst to FIG. 1, a wellcasing member 5 is shown installed in an oil well with a production pipeor inner tubing member 6 extending down through the casing generallyconcentric therewith. Packing means, such as the packer 7, are providedbetween tubing 6 and casing 5 at a lower end thereof to seal well fluidbelow the packer 7 and to form a well uid receiving lreservoir 8 abovethe packing means. Reservoir 8 extends upwardly from packer 7 in thecasing annulus formed between the casing 5 and the inner concentrictubing 6 above packer 7. A lower casing annulus 9 is formed below packer7 between the inner or production tube 6 and the casing 5, which is opento the well fluid and the high pressures exerted by such uid. In theembodiment shown, the bottom of tubing 6 is closed to the well and aplurality of ports 10 are provided to allow well fluid to pass from theannulus 9 into the interior of tubing 6. The provision of such ports 10is optional since the bottom end of tubing 6 could be lmade open ratherthan closed, as shown.

Tubing plug 11 is provided in the inner or production tube 6 at a pointspaced above the packer 7. Plug 11 is provided to form a pump inletchamber 12 in the tubing bore above plug 11 and a well fluid receivingchamber 13 in the tubing bore below plug 11.

Passage means a-re provided to interconnect the reservoir 8 with thewell fluid receiving chamber 13 which is Such means in the preferredembodiment include a vertical passage or stand pipe 14 which has itslower end connected into an upper portion of chamber 13 at a pointthereof between plug 11 and the packer 7. Vertical passage or stand pipe14 extends upwardly from its lower end between the tubing 6 and casing 5within the reservoir 8. Passage 14 opens into the reservoir 8 through anaperture at an upper end which is vertically spaced from packer 7 withinthe reservoir 8 by as much as 100 feet and is preferably relatively near(such as 5 to 10 feet) to a predetermined normal fluid level for theiluid within the reservoir, indicated at 15.

Well fluid with gas in solution enters the casing annulus 9 below packer7, passes through ports 10 into the `well Huid inlet chamber 13 belowplug 11, rises due to well pressure through the vertical passage meansor stand pipe 14 to an upper portion of reservoir 8 where it isdischarged into reservoir 8 under relatively low pressure. Gas comingout of solution passes upwardly through the casing annulus. The wellfluid settling in the reservoir 3 is drawn through the ports 16 intubing 6, into the pump inlet chamber 12. Inlet 16 is at a lower portionof the reservoir 8 where higher fluid pressures exist due to the head offluid in the reservoir. The well fluid is then evacuated by the pump 17and forced upwardly through tubing 16 to the surface of the well. Pump17 may be of any conventional form of well pump, as the well known formof lluid operated well pump, employing sucker rods or macaroni tube 18.

The level of the well fluid within reservoir 8 is maintained at apredetermined level above the top opening of the vertical passage meansto promote the escape of gases from the well fluid introduced into thereservoir. Means for controlling the reservoir fluid level are provided,such means comprising a liquid level control, indicated generally at 20,according to the invention. It is preferred in the embodiment of FIGS. land 2 to position the liquid level control, indicated generally at 20,within the reservoir and at an upper portion thereof where it issubjected to the reservoir fluid pressures present in the upper portionsof the reservoir, rather than at a lower portion of the reservoir whereiluid pressures are relatively much higher. Normally, the length of thevertical passage or stand pipe 14 is between about 20 and about 30 feetbut it may be as long as 10() feet. The liquid level control valve,according to the invention, may be disposed in this relatively high areaof reservoir 8 and be operable by the relatively low reservoir iluidpressures present ther-ein due to the ability of the control to regulatethe high pressure well fluid passing therethrough in response to changesin the relatively small fluid pressures in the upper portion of thereservoir.

Reservoir fluid level control, indicated generally at 20 and as shown indetail in FIG. 2, is provided with a main valve body 21 having a sideinlet tube 22. Inlet tube 22 is adapted at its lower end to be attachedto the upper end of vertical passage means 14 and introduces the welluid passing upwardly through such passage means into a generally centralportion of the cylindrical open ended body 21. A plurality of ports 23in the walls of body 21 above the inlet tube 22 allow the well fluidpassing upwardly through passage means 14, inlet tube 22 and the body 21to pass into the reservoir 8, as well as through the lower open end ofbody 21. A pressure chamber body 24 is provided at an upper end of valvebody 21, removably attached to body 21 by a threaded connection thereto,forming a pressure chamber 25 therein adapted to be precharged with gas.Pressure or diaphragm chamber 25 may be precharged through the dill core26, at an upper end of body 24. A pipe plug 27 seals such upper end as asafety measure to retain the charge within chamber 25 and to keepexternal pressure out should the well pressure cause a reservoirpressure exceeding the charging pressure. Such charging pressures arenormally about pounds per square inch. The precharging of chamber 25acts as a diaphragm biasing means to maintain the valve means, indicatedgenerally at 30 and the diaphragm means indicated generally at 40, in anopen position allowing the passage of well fluid from inlet tube 22through the ports 23 and the lower open end of body 21 into reservoir 8,as subsequently described. When the fluid pressure in the reservoir 8 inthe upper portion thereof near the normal reservoir fluid level risessufficiently to overcome the bias of such precharging, the valve means30 close, preventing further ow of well Huid into reservoir 8. Valvemeans 30 are retained closed until the pump 12 removes sufficient fluidfrom reservoir 8 to lower the iluid pressure within the reservoir byreturning the level of reservoir fluid to the predetermined normal levelindicated at 15 in FIG. l.

Valve means are disposed within reservoir 8 below the normal fluid levelin the reservoir and are interconnected between the vertical passagemeans 14 at its upper end or aperture and the reservoir 8. Such valvemeans, indicated generally at 30, include an upper poppet 31 and a lowerpoppet 32 axially spaced apart upon a stem 33 by a poppet spacer 34. Anut 35 threadably attached to the stem 33 maintains the poppets in suchspaced relation upon the stem 33. Stem 33 passes through a pair ofspaced opposed ports formed in an upper valve seat 36 and an adjustablelower valve seat 37 which is threadably received in the lower portion ofbody 21. Sealing means, such as Ian O-ring seal or preferably a moldedrubber, are provided on the valve seats 36 and 37, respectively, asshown in FIG. 2 to prevent the passage of `sand and fluid between theseats and the body 21. Similarly, -a sealing means, preferably of moldedrubber are provided on the upper surface of each of the poppets 31 and32 as shown in FIG. 2 'at 31 and 32', respectively. Valve poppet 31 isdisposed below the upper ported Valve seat 36, being between or inwardlyof the two valve seats. Valve poppet 32 is disposed below the lowerported valve seat 37, being below or outwardly of the spaced portedvalve seats. Therefore, well fluid under high pressure passing frominlet tube 22 into the interior of body 21 attempts to force the upperpoppet closed and lower poppet open, effecting a general balancing ofthe high well uid pressures. The well uid then passes from the interiorof body 21 at the inlet 22 through the upper ported valve seat 36 intothe discharge chamber 80 opening to reservoir 8 through ports 23 andthrough the lower ported valve seat 37 into the reservoir 8.

Preferably, the effective hydrostatic pressure exerted on the poppets 31and 32 by the well iuid within body 21 is slightly unbalanced to providea resultant closing force on the poppets due to well pressure. If thepoppets 31 and 32 are provided identically with identical molded rubbersealing means 31 and 32', the valve will be perfectly hydrostaticallybalanced when closed. We have found that by providing a slightly largersealing means 31 (having a greater surface area than the bottom sealingmeans 32) than means 32, a slight unbalancing of the valve means may beattained. Thus, when in a closed position, the valve means is heldclosed by the well fluid pressure in body 21, but under a considerablysmaller force than the total force being exerted on the valve means bythe well fluid.

An upper portion or head of stem 33 is associated with diaphragm means,indicated generally at 40, to cause the opening and closing of the Valvemeans, indicated generally at 30, to be responsive to fluid pressurewithin the reservoir 8 as determined by the liquid level withinreservoir 8. Diaphragm means, indicated generally at 40, may include thediaphragm 41 retained between a pair of upper retainer rings, outerretainer ring 42 and inner retainer ring 43, and a pair of lowerretainer rings, lower retainer ring 44 and valve stem retainer ring 45.The outer (upper and lower) retainer rings 42 and 44, are iixedly heldwithin body 21, upper outer ring 42 abutting the body 24 at its upperportion and outer lower retainer ring 44 abutting a perforated spacerring 46 xedly held within body 21 by the upper ported valve seat 36.Seat 36 may rest on a ledge formed in the body 21. Upper inner retainingring 43 and the diaphragm means, indicated generally at 40, are biaseddownwardly by the precharged gas within chamber 25.

6 retaining ring 44 may be provided to guide the stem in its verticalmovement between open and closed positions.

Diaphragm 41 forms a primary seal between the pressure chamber 25 andthe fluid discharge chamber 29, the diaphragm reacting to variances inpressure between the two chambers. A secondary seal is effected betweenthe lower inner retaining ring 45 formed in the stem 33 and the lowerouter retaining ring 44. When the valve is in the open position as shownin FIG. 2, a smaller area on the valve stern ring 45 is exposed to thereservoir pressure than when the valve is open and the lower surface ofthe diaphragm is exposed. Thus, the valve is given a snap action as soonas the pressure in chamber 29 reaches a point which causes a break inthe secondary seal effected between the ring 45 and the ring 44. Sincethe actuating pressure acts on the larger surface of diaphragm 41,effecting a greater force on stem 33, than that on ring 45.

In operation, the control apparatus is lowered into the casing annulusdown through the well fluid standing therein. As the apparatus islowered, the increase in fluid pressure exerted through ports 23 on thebottom of diaphragm 41 tends to close the valve poppets upon theirrespective seats. After insertion of the packing means 7 causing wellfluid to pass through the tubing annulus 13 and vertical passage means14, the well fluid pressure in body 21 tends to keep the valve poppets31 and 32 closed as well as diaphragm means 40. As well iluid is pumpedfrom the reservoir formed between the tubing and casing walls, thepressure on the outer surface of diaphragm 41, acting through ports 23,decreases until the pressures on either side of diaphragm 41 areequalized. However, further reduction of the reservoir pressure isrequired to allow the pressure in the pressure chamber 25 to move thediaphragm 41 and poppets 31 and 32 due to the unbalancing thereof. Whenthe effect of the unbalancing is overcome, the poppets 31 and 32 willsnap open since once the poppets are un- Seated, the unbalancing of thehydrostatic pressures on the sealing means 31 and 32 is lost. Thus, aquick positive action of the valve is attained upon opening. Also, wehave noticed Ia slight elongation of the stem 33 between the poppetswhen very high well pressures are encountered which causes the lowerpoppet to be unseated. By unbalancing the effective hydrostaticpressures upon the poppets as hereinbefore described, the poppets areurged upwardly under higher well fluid pressures in body 21, compressingthe seal 31 more, and maintaining seal 32 closed even where a slightelongation of the stem 33 occurs. When the fluid level in the reservoirincreased to `an undesirable height, increasing the pressure exerted onthe previously described primary sealing4 means of the diaphragm means40, the valve will snap closed as previously explained.

An alternative exemplary embodiment of the apparatus for removing wellfluid from a well, including a reservoir uid level control device,according to the invention is shown in FIGS. 3, 4, 4a, 5 and 5a. In theprior exemplary embodiment of FIGS. 1 and 2, the fluid level control,indicated generally at 20, cannot be brought to the surface forservicing without pulling the tubing, Ia very costly operation. In theembodiment of FIGS. 3, 4 and 5, the fluid level control device,indicated generally at 120, is adapted to be readily removed from thewell without removing the tubing string 106. In general. this isaccomplished by suspending the iluid level control from the deep wellpump and providing a special tubing nipple on the bottom end of thetubing string, as described hereinafter. The fluid level control andtubing nipple can also be run on wire line tools to be set below thepump and retrieved with a wire line after the pump has been pulled.

Referring rst to FIG. 3, the iluid level control, indicated generally at120, may be provided with a convenrinner tubing string 106 below thetubing plug 111.

tional lockdown assembly, indicated generally at 70. The lockdownassembly serves to hold the fluid level control in position within thegenerally smooth inner surfaced tubing string when in lowered positionand may be provided with a wire line lishing deck 71 adapted tofacilitate removal of the control means by dropping a Wire line thereonand raising it. Alternatively, a direct rigid connection between thebottom end of the pump 117 and control means can be provided such thatremoval of the pump 117 by pulling up the sucker rods or macaroni tube118 extending from the pump to the surface, will concurrently remove thecontrol means, indicated generally at 120. Preferably, the connectionbetween the pump and control means is flexible and may be provided asshown in FIG. with a slip joint, indicated generally at '75.

Referring again to FIG. 3, a Well casing member 105 is shown installedin an oil well with a production pipe or inner tubing string 106extending down through the casing generally concentric therewith.Packing means., such as the packer 107, are provided between the tubingstring 106 and the ca-sing tube 105 at a lower end thereof to seal Welliluid below the packer 107 and to form a well fluid receiving reservoir108 above the packing means, as in the embodiment of FIGS. 1 and 2. Alower casing annulus 109, formed below packer 107 between the inner orproduction tubing string 106 and the casing 105, is open to the welllluid at relatively high well pressures. The bottom end of theproduction tubing string 106 may be closed to the well with a pluralityof ports 110 as shown in FIG. 3 or it may be left open to receive Wellfluid into the well iluid receiving chamber 113 formed within the In theexemplary embodiment of FIGS. 3, 4 and 5, the inner .tubing bore 112above the tubing plug 111 is adapted to receive the fluid level controlmeans, indicated generally at 120, and the deep well pump 117, as bestshown in FIG. 3. Both the deep well pump 117 and the uid level controlmeans, indicated generally at 120, may be withdrawn from the tube 5 andreinserted therein without disturbing the positioning of the productiontubing string 106.

Vertical passage means are provided to interconnect the reservoir 108with the well uid. Such means in the present exemplary embodimentcomprise a primary vertical passage, such as bypass pipe 50, adapted tointerconnect the chamber 113 and control means, and a secondary verticalpassage, such as the stand pipe 57, to interconnect the control meanswith reservoir 108.

In operation, the well iluid passes from chamber 113 through primaryvertical passage means, as bypass pipe 50, into the fluid level controlmeans, indicated generally at 120, and then upwardly through thesecondary vertical passage means, as stand pipe 57, to an upper portionof reservoir S where the entrapped gases may escape under conditions ofrelatively low fluid pressure, the upper end of the rsecondary passagemeans being relatively near the normal fluid level 115 in reservoir 108.The primary and secondary passages thus provide a vertical passage meansas in the embodiment of FIGS. l and 2 except that the valve means of thepresent removable control device ris disposed in an intermediary portionof the passage means, rather than at an upper portion.

According to the invention, the vertical passage means may be providedon a special tubing nipple 206 shown in detail in FIGS. 5 Vand 5a.Special tubing nipple 206 is adapted to be secured to the lower end ofthe tubing string 106 at about the location therein that the pump 117 isto be positioned, as shown in FIG. 5. The tubing nipple 206 is providedwith the plug 111 forming tubing bore chamber 112 above and the tubingbore chamber 113 below and is adapted to be lowered into the packingmeans 107. The bypass pipe 50, or primary passage means, is secured tothe side of nipple 206 with a lower end communicating with tubing borechamber 113. The upper end of the bypass pipe, passing around the plug111, opens into a valve inlet chamber delined by the packing means 51and 52, the control device and the interior of tubing nipple 206. Suchvalve inlet chamber is in iluid communication with the valve inlet ports54 regardless of the positioning of the ports provided only that thepacking means 51 and 52 straddle the outlet or upper end of the bypasspipe 50.

The secondary vertical passage means, as stand pipe 57, may be disposedon the special tubing nipple 206 as shown in FIG. 5a with its lower endcommunicating with the tubing bore chamber or valve outlet chamber 112to receive fluid ow from valve outlet ports 55. The upper exhaust ports56 on the control means exhaust into a chamber formed within nipple tube206 between the control means, packing means 51 and vertically spacedpacking means 58. This valve outlet chamber is in uid communication withthe secondary vertical passage means or stand pipe 57 at a pointvertically spaced above the lower end of pipe 57. Such spacing isgenerally equal to the spacing between ports 56 and 55 on the controlmeans. The upper end of stand pipe 57 carries ythe well fluid Well abovetubing ports 116 in the tubing nipple 206 directly below the pump 117.Well iluid in reservoir 108 may thus pass into the interior of thetubing nipple 206 at a point in the tubing string 106 well below thenormal liquid level of the reservoir liquid.

Connector means to attach `the liquid level control to the bottom ofpump 117 may be provided such as the slip joint connecting means showngenerally at 75 in FIG. 5. A pump nipple 72 depending from pump 117 maybe provided with a key member 73 adapted to slip into the housing 74disposed upon the top portion of the control means indicated generallyat 120. Pump inlet ports 76 vare provided in pump nipple 72, as shown inFIG. 5, to

withdraw well fluid from the interior or bore of tubing nipple 206 abovethe packing means 53 and pump it to the surface.

Referring now to FIGS. 4 and 4a, the alternative exemplary embodiment ofa uid level control means, according to the invention and as showngenerally at 120 in FIG. 3, is provided with a body assembly including apressure chamber and a generally cylindrical valve body. Such valve bodymay include an upper valve body portion 61, a center valve body portion62, a lower valve body portion 63 and a bottom nose portion 64.

Pressure chamber body portion 60 is provided in an upper end ofthe bodyassembly, removably attached thereto by a threaded connection, and formsa pressure chamber therein adapted to be precharged with gaa as in theembodiment of FIGS 1 and 2. A drill core 126 at the upper end ofpressure chamber body 124 and a pipe plug 127 sealing such upper end areprovided for introducing gas into the chamber 125. In addition to theprecharged gas within chamber 125, acting as a diaphragm biasing meansto maintain the valve means indicated generally at 130 and a diaphragmmeans indicated generally at 140 in an open position, spring means 129may be provided to hold the valve in an open position should the gaswithin chamber 125 be accidentally evacuated. Spring means 129 areoptional.

Valve means, indicated generally at 130, include an upper poppet 131 anda lower poppet 132 axially spaced apart upon a stem 133 by a poppetspacer 134. A nut 135 threadably attached to the lower end of stem 133maintains the poppets in assembled relation upon stem 133. Stem 133passes through a pair of spaced, opposed ports formed in an upper valveseat 136 and an adjustable lower valve seat 137 which is threadablyreceived in the lower valve body portion 63 of the control bodyassembly. Sealing means, such as the O-rings 65, are provided on thevalve seats 136 and 137, poppets 131 and 132 and at the juncturesbetween the various body assembly body portions as shown in FIGS. 4 and4a. In addition, sand seal means 68 are preferably provided above thepacking means as indicated in FIG. 4a to stop sand from packing betweenthe control device and the inner bore of tubing nipple 206. If allowedto settle in these areas, the' sand would tend to freeze the controlinto the tubing nipple making it impossible to remove it to the surface.

Well iluid entering the ports 54 in the central valve body portion .62from the bypass pipe 50 pass both upwardly and downwardly within thecontrol body assembly, producing a slightly unbalanced hydrostaticpressure upon the poppets 131 and 132 as in the rst embodimentdisclosed. The well fluid then, passes from the interior of the controlbody assembly through the upper ported valve seat 136 into a dischargechamber 180 opening to the reservoir 108 through the ports 123 andvertical passage means 57 and downwardly through the lower ported valveseat 137 opening into the reservoir 108 through the ports S of lowernose body portion 64 and the vertical passage means 57.

The upper portion or head of stem 133 is associated with diaphragmmeans, indicated generally at 140 as in the embodiment of FIGS. l and 2,to cause the opening and closing of the hydrostatically balanced valvemeans, indicated generally at `130, in response to variations in thefluid pressure within reservoir 108 as determined by the liquid level,indicated at 115, within the reservoir. The diaphragm means may includethe diaphragm 141 retained lat its outer edges between a pair of opposedouter retainer rings 142 and 144. The inner portions of diaphragm 141are maintained between a pair of opposed inner retainer rings 143 andvalve stern retainer ring 145. Ring 142 abuts at its upper surface onthe pressure chamber body 60 while lower outer ring 144 abuts at itslower portion against a ledge formed within the upper valve body portion61. It should be noted that in the embodiment of FIGS. 4 and 4a, thelower outer retainer ring 144 includes integrally formed stem guideportions 149, a lower perforated ring portion and upper valve seat 136.Thus, the lower retainer ring 44, slotted stem guides 49, perforatedspacer ring 46 and upper ported valve seat 36 of the embodiment of FIGS.l and 2 is provided in an integrally formed unit 67 in theembodiment ofFIGS. 4 and.4a. Upper inner retaining ring 143 is biaseddownwardly bythe precharged gas within chamber 25 and the optional spring means 129abutting against the washer 147 positioned between the spring 129 andring 143. As in the embodiment of FIGS. 1 and 2, diaphragm 141 forms aprimary seal between the pressure chamber 125 and the fluid dischargechamber 180, the diaphragm reacting to variances in pressure between thetwo chambers. A secondary seal is also effected between the lower innerretaining ring 14S mounted on the stem 133 and the lower outer retainingring portion 144 of unit 67. Thus, a snap action is given to the valvemeans as in the embodiment of FIGS. l and 2.

From the foregoing detailed descriptions of exemplary embodiments of theapparatus for handling high pressure, high gas saturated well fluid andthe reservoir liquid level control device employed therein, it may beseen that such Well fluid is easily introduced into the well apparatusreservoir in readily controlled amounts maintaining the liquid level ofthe reservoir at a predetermined level. In addition, the ow of fluidthrough the valve means of the control device is hydrostaticallybalanced so that actuation of the valve means may be readily and easilyaccomplished by the pressure sensing device, operating under the forceof relatively low reservoir pressures upon the diaphragm means. Further,in the alternative exemplary embodiment, the hydrostatically balancedvalve means, pressure sensing means, etc. of the control device may allbe removed from the well apparatus without disturbing the casing andtubing string walls, including the tubing nipple and vertical passagemeans provided thereon.

Having thus described the invention in detail by reference to exemplaryembodiments thereof and noting that other modiiications, embodiments,alternatives and refinements thereof may be made within the scope of theinvention, what is claimed and new and desired to be secured by LettersPatent is:

1. In an apparatus for removing well iluid from a well including spaced,vertical casing and tubing walls forming a reservoir to receive wellfluid preparatory to introduction into a well pump, the provision of:

vertical passage means interconnecting said reservoir with well iiuidfrom said well, said passage means extending upwardly in said reservoirabove the pump and opening into said reservoir at an upper portionthereof below a normal uid level;

valve means associated with said passage means to control flow of iluidinto said reservoir; and

pressure sensitive means responsive to changes in iluid level in saidreservoir to operate said valve means to closed position upon the riseof well Huid above a predetermined level within said reservoir.

2. The apparatus of claim 1 wherein said valve means is disposed withinsaid reservoir at an upper end of said vertical passage means below thenormal iluid level in said reservoir and said pressure sensitive meansis disposed in said reservoir above said valve means.

3. The apparatus of claim 1 wherein said valve means comprises:

a valve body having an inner chamber and two aligned spaced portsopening said chamber to said reservoir;

a valve stem through said aligned ports associated at one end with saidpressure sensitive means;

a pair of valve poppets on said stem, axially spaced apart thereon tocooperate with said ports, one of said poppets beingon the inner side ofone of said ports and the other of said poppets being on the outer sideof the other of said ports.

4. The apparatus of claim 3 wherein the effective hydrostatic pressurereceiving area of said one poppet is greater than that of said otherpoppet when said poppets are in closed position.

5. The apparatus of claim 1 wherein said pressure sensitive meanscomprises:

a pressure chamber body mounted on said valve means vand receiving anupper portion of said valve stem; diaphragm means associated with saidupper portion of said valve stem;

passage means interconnecting one side of said diaphragm means with saidreservoir; and

means within said chamber body to bias said diaphragm against iiuidpressure of said reservoir eX- erted on said one side of said diaphragm.

6. A device for introducing well tluid into a deep well pump,comprising:

a casing member;

an inner, generally concentric tubing member;

packing means between said tubing and casing to seal well uid below saidpacking means and form a well fluid receiving reservoir above saidpacking means;

a plug in said tubing above said packing means;

a deep well pump in said tubing above said plug and communicative withsaid reservoir;

passage means interconnecting said reservoir with well iluid in saidwell, said passage means including a vertical passage interconnected atits lower end with said tubing at a point between said plug and packingmeans, extending upwardly between said tubing and casing within saidreservoir and opening into said reservoir at an upper aperturevertically spaced above said packer means, plug and pump;

valve means disposed within said reservoir below a normal tluid level insaid reservoir and interconnected with said passage means upperaperture; and

means within said reservoir for controlling said valve in response tochanges in the level of fluid in said reservoir to maintain apredetermined normal fluid level.

7. A device as in claim 6 wherein said valve means comprises:

a valve body having an inner chamber and two aligned spacedports'opening said chamber to said reservoir;

a valve stem through said aligned ports associated at one end with saidpressure sensitive means; and

a pair of valve poppets on said stem, axially spaced apart thereon tocooperate with said ports, one of said poppets being on the inner sideof -one of said ports and the other of said poppets being on the outerside of the other of said ports and where well iluid pressure in saidvalve means is hydrostatically unbalanced on said poppets.

8. A device as in claim 6 wherein the pressure sensitive meanscomprises:

a pressure chamber body mounted on said valve means and receiving anupper portion of said valve stem;

diaphragm means associated with said upper portion of said valve stem;

passage means interconnecting one side of said diaphragm means with saidreservoir; and

means within said chamber body to bias said diaphragm against fluidpressure of said reservoir exerted on said one side of said diaphragm.

9. In the apparatus of claim 1, the provision of a tubing nipple at alower end of the tubing walls having a plurality of vertically spacedapertures therein and wherein said vertical passage means includesprimary and secondary passages mounted on sides of said nipple and saidhydrostatically balanced valve means is removably received within saidnipple intermediate said primary and secondary passages.

10. A device for introducing well iluid into a well pump, comprising:

vertical spaced casing and tubing Walls forming a reservoir therebetweenfor receiving well fluid from a well;

a pump disposed between a lower portion of said tubing walls andcommunicative with a lower portion of said reservoir;

Vertical passage means interconnecting said reservoir with well iluidfrom said well, said passage means extending upwardly in said reservoirabove said pump and opening into said reservoir at an upper portionthereof but below the normal i'luid level in said reser- Voir;

valve means disposed within said reservoir at said upper portion beingbelow the normal iluid level in said reservoir and interconnected withsaid passage means; and

pressure sensitive means in said reservoir and associated with saidvalve means adapted to operate said valve to maintain a predeterminedlevel of fluid within said reservoir.

11. In an apparatus for removing well fluid from a deep well includingspaced, vertical casing and tubing walls forming a reservoir to receivewell fluid preparatory to introduction into a deep well pump removablydisposed within said tubing walls, the provision of a tubing nippledepending from a lower end of said tubing wall, said tubing nipplehaving vertically spaced apertures in a side wall thereof;

Vertical passage means associated with said tubing nipple tointerconnect said reservoir with a source of well Huid through saidtubing nipple side Wall apertures;

valve means removablylreceivable within said tubing nipple having inletand outlet means for alignment with said tubing nipple side Wallapertures when said valve means is received within said tubing nipple,said valve means controlling fluid ow through said vertical passagemeans between said source of well Huid and said reservoir when removablyreceived within said tubing nipple; and

fluid pressure sensitive means removably receivably within said tubingnipple and associated with said valve means for operating said Valvemeans in response to changes in the level of well iluid in saidreservoir, said tubing nipple having aperture means in a side wallthereof communicating iluid pressure of said reservoir to said tluidpressure sensitive means when said fluid pressure sensitive means isreceived within said tubing nipple.

References Cited bythe Examiner UNITED STATES PATENTS 1,959,621 5/34 Fry103-5 2,429,848 10/47 Smith 10S-179 3,055,386 9/62 Moore 137-4033,071,150 1/63 Whitlock 137-391 KARL J. ALBRECHT, Primary Examiner.

LAURENCE V. EFNER, IOSEPH H. BRANSON IR.,

Examiners.

1. IN AN APPARATUS FOR REMOVING WELL FLUID FROM A WELL INCLUDING SPACED,VERTICAL CASING AND TUBING WALLS FORMING A RESERVOIR TO RECEIVE WELLFLUID PREPARATORY TO INTRODUCTION INTO A WELL PUMP, THE PROVISION OF:VERTICAL PASSAGE MEANS INTERCONNECTING SAID RESERVOIR WITH WELL FLUIDFROM SAID WELL, SAND PASSAGE MEANS EXTENDING UPWARDLY IN SAID RESERVOIRAT AN UPPER PORTION AND OPENING INTO SAID RESERVOIR AT AN UPPER PORTIONTHEREOF BELOW A NORMAL FLUID LEVEL; VALVE MEANS ASSOCIATED WITH SAIDPASSAGE MEANS TO CONTROL FLOW OF FLUID INTO SAID RESERVOIR; AND PRESSURESENSITIVE MEANS RESPONSIVE TO CHANGES IN FLUID LEVEL IN SAID RESERVOIRTO OPERATE SAID VALVE MEANS TO